
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
// 
//   http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

/**
 * AUTO-GENERATED FILE. DO NOT MODIFY.
 */

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
// 
//   http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.
import { isFunction, isString } from 'zrender/lib/core/util.js';
var samplers = {
	average: function (frame) {
		var sum = 0;
		var count = 0;

		for (var i = 0; i < frame.length; i++) {
			if (!isNaN(frame[i])) {
				sum += frame[i];
				count++;
			}
		} // Return NaN if count is 0

		return count === 0 ? NaN : sum / count;
	},
	sum: function (frame) {
		var sum = 0;

		for (var i = 0; i < frame.length; i++) {
			// Ignore NaN
			sum += frame[i] || 0;
		}

		return sum;
	},
	max: function (frame) {
		var max = -Infinity;

		for (var i = 0; i < frame.length; i++) {
			frame[i] > max && (max = frame[i]);
		} // NaN will cause illegal axis extent.

		return isFinite(max) ? max : NaN;
	},
	min: function (frame) {
		var min = Infinity;

		for (var i = 0; i < frame.length; i++) {
			frame[i] < min && (min = frame[i]);
		} // NaN will cause illegal axis extent.

		return isFinite(min) ? min : NaN;
	},
	// TODO
	// Median
	nearest: function (frame) {
		return frame[0];
	}
};

var indexSampler = function (frame) {
	return Math.round(frame.length / 2);
};

export default function dataSample(seriesType) {
	return {
		seriesType: seriesType,
		// FIXME:TS never used, so comment it
		// modifyOutputEnd: true,
		reset: function (seriesModel, ecModel, api) {
			var data = seriesModel.getData();
			var sampling = seriesModel.get('sampling');
			var coordSys = seriesModel.coordinateSystem;
			var count = data.count(); // Only cartesian2d support down sampling. Disable it when there is few data.

			if (count > 10 && coordSys.type === 'cartesian2d' && sampling) {
				var baseAxis = coordSys.getBaseAxis();
				var valueAxis = coordSys.getOtherAxis(baseAxis);
				var extent = baseAxis.getExtent();
				var dpr = api.getDevicePixelRatio(); // Coordinste system has been resized

				var size = Math.abs(extent[1] - extent[0]) * (dpr || 1);
				var rate = Math.round(count / size);

				if (isFinite(rate) && rate > 1) {
					if (sampling === 'lttb') {
						seriesModel.setData(data.lttbDownSample(data.mapDimension(valueAxis.dim), 1 / rate));
					}

					var sampler = void 0;

					if (isString(sampling)) {
						sampler = samplers[sampling];
					} else if (isFunction(sampling)) {
						sampler = sampling;
					}

					if (sampler) {
						// Only support sample the first dim mapped from value axis.
						seriesModel.setData(data.downSample(data.mapDimension(valueAxis.dim), 1 / rate, sampler, indexSampler));
					}
				}
			}
		}
	};
}